Geology topics

Jeffrey J. Steuer

Publications and source records attributed to Jeffrey J. Steuer.

5 recordsLinked to original sources

USGS2010

Determination of biologically significant hydrologic condition metrics in urbanizing watersheds: an empirical analysis over a range of environmental settings

We investigated the relations among 83 hydrologic condition metrics (HCMs) and changes in algal, invertebrate, and fish communities in five metropolitan areas across the continental United States. We used a statistical approach that employed Spearman correlation and regression tree analysis to identify five HCMs that are strongly associated with observed biological variation along a gradient of urbanization. The HCMs related to average flow magnitude, high-flow magnitude, high-flow event frequency, high-flow duration, and rate of change of stream cross-sectional area were most consistently associated with changes in aquatic communities. Although our investigation used an urban gradient design with short hydrologic periods of record (≤1 year) of hourly cross-sectional area time series, these five HCMs were consistent with previous investigations using long-term daily-flow records. The ecological sampling day often was included in the hydrologic period. Regression tree models explained up to 73, 92, and 79% of variance for specific algal, invertebrate, and fish community metrics, respectively. National models generally were not as statistically significant as models for individual metropolitan areas. High-flow event frequency, a hydrologic metric found to be transferable across stream type and useful for classifying habitat by previous research, was found to be the most ecologically relevant HCM; transformation by precipitation increased national-scale applicability. We also investigated the relation between measures of stream flashiness and land-cover indicators of urbanization and found that land-cover characteristic and pattern variables, such as road density, percent wetland, and proximity of developed land, were strongly related to HCMs at both a metropolitan and national scale and, therefore, may be effective land-use management options in addition to wholesale impervious-area reduction.

Milwaukee-Green Bay; Boston; Raleigh; Atlanta; Bir↗

USGS2010

A generalized watershed disturbance-invertebrate relation applicable in a range of environmental settings across the continental United States

It is widely recognized that urbanization can affect ecological conditions in aquatic systems; numerous studies have identified impervious surface cover as an indicator of urban intensity and as an index of development at the watershed, regional, and national scale. Watershed percent imperviousness, a commonly understood urban metric was used as the basis for a generalized watershed disturbance metric that, when applied in conjunction with weighted percent agriculture and percent grassland, predicted stream biotic conditions based on Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness across a wide range of environmental settings. Data were collected in streams that encompassed a wide range of watershed area (4.4-1,714 km), precipitation (38-204 cm/yr), and elevation (31-2,024 m) conditions. Nevertheless the simple 3-landcover disturbance metric accounted for 58% of the variability in EPT richness based on the 261 nationwide sites. On the metropolitan area scale, relationship r ranged from 0.04 to 0.74. At disturbance values 15. Future work may incorporate watershed management practices within the disturbance metric, further increasing the management applicability of the relation. Such relations developed on a regional or metropolitan area scale are likely to be stronger than geographically generalized models; as found in these EPT richness relations. However, broad spatial models are able to provide much needed understanding in unmonitored areas and provide initial guidance for stream potential.

Portland; Salt Lake City; Denver; Dallas-Fort Wort↗

USGS2001

Use of a watershed-modeling approach to assess hydrologic effects of urbanization, North Fork Pheasant Branch basin near Middleton, Wisconsin

The North Fork Pheasant Branch Basin in Dane County, Wisconsin is expected to undergo development. There are concerns that development will adversely affect water resources with increased flood peaks, increased runoff volumes, and increased pollutant loads. To provide a scientific basis for evaluating the hydrologic system response to development the Precipitation Runoff Modeling System (PRMS) was used to model the upper Pheasant Branch Creek watershed with an emphasis on the North Fork Basin. The upper Pheasant Branch Creek (18.3 mi2; 11,700 acres) Basin was represented with 21 Hydrologic Response Units (daily time step) and 50 flow planes (5-minute time steps). Precipitation data from the basin outlet streamflow-gaging station located at Highway 12 and temperature data from a nearby airport were used to drive the model. Continuous discharge records at three gaging stations were used for model calibration. To qualitatively assess model representation of small subbasins, periodic reconnaissance, often including a depth measurement, was made after precipitation to determine the occurrence of flow in ditches and channels from small subbasins. As a further effort to verify the model on a small subbasin scale, continuous-stage sensors (15-minute intervals) measured depth at the outlets of three small subbasins (500 to 1,200 acres). Average annual precipitation for the simulation period from 1993 to 1998 was 35.2 inches. The model simulations showed that, on average, 23.9 inches were intercepted by vegetation, or lost to evapotranspiration, 6.0 inches were infiltrated and moved to the regional ground-water system, and 4.8 inches contributed to the upper Pheasant Branch streamflow. The largest runoff event during the calibration interval was in July 1993 (746 ft3/sec; with a recurrence interval of approximately 25 years). Resulting recharge rates from the calibrated model were subsequently used as input into a ground-water-flow model. Average annual recharge varied spatially from 2.3 inches per year in the highly impervious commercial/industrial area to 9.7 inches per year in the undeveloped North Fork Basin with an average overall recharge rate of 8.1 inches per year. Two development scenarios were examined to assess changes in water-budget fluxes. In scenario A, when development was predominantly low-density residential with 5 to 10 percent commercial development along principal roadways, mean annual streamflow increased by 53 percent, overland flow increased by 84 percent, base flow decreased by 15 percent and annual recharge to the regional ground-water system was reduced by 10 percent. In development scenario B, the entire North Fork and intervening area basins contained 50 percent commercial and 50 percent medium density residential land use. Annual storm runoff increased by over 450 percent. The ground-water model for the Pheasant Branch that used the scenario B recharge rates simulated a lowered water table with zero base flow and that flow from Frederick Springs would be reduced 26 percent from present-day (1993?98) conditions.An additional example application of the model evaluated locations of flood detention ponds and potential recharge areas that may mitigate the changes in flood peaks and ground-water recharge resulting from urbanization. From February 1998 through July 1998, water-quality samples were collected by use of stage-activated automated samplers. Median suspended- sediment concentrations were similar between the North and South Fork Basins (194 and 242 mg/L, respectively); however, for other constituents, North Fork values were considerably higher: median phosphorus concentrations by 4 times (1.5 and 0.35 mg/L), median ammonia concentrations by 13 times (1.9 and 0.14 mg/L), and the phosphorus-to-sediment ratio by more than 6 times (21 and 3.1 mg/g).

Wisconsin↗

USGS2000

A mass-balance approach for assessing PCB movement during remediation of a PCB-contaminated deposit on the Fox River, Wisconsin

The U.S. Geological Survey, in cooperation with the Wisconsin Department of Natural Resources, collected water samples during the September 1 - December 15, 1999 removal of sediment contaminated with polychlorinated biphenyls (PCBs) from a reach of the Lower Fox River designated Sediment Management Unit (SMU) 56/57. Results of analyses of the samples, along with monitoring activities of several other organizations, were used to delineate and compare PCB mass pathways during the cleanup effort (fig. 1). Results indicate that the cleanup at SMU 56/57 had the following effect on PCB mass: dredging permanently removed more than 650 kg (1441 lb) of PCBs, transported 14.5 kg (32 lb) downstream, and volatilized 2.6 kg (5.7 lb) to the atmosphere; associated activities on the shore returned 0.1 kg (0.3 lb) to the river. This report documents the USGS data-collection efforts and details the mass-balance approach for PCB pathway delineation.

Wisconsin↗

USGS1996

The Fox River PCB transport study: Stepping stone to a healthy Great Lakes ecosystem

Polychlorinated Biphenyls (PCBs) in the Great Lakes Despite being banned since the 1970's, polychlorinated biphenyls (PCBs) continue to pose a threat to the environment because of their persistence and toxicity to organisms ranging from minute algae to fish, waterfowl, and human beings. PCBs, a set of 209 related chlorinated organic compounds, had various industrial uses such as in hydraulic fluids, cutting oils, sealants, and pesticides. Despite the manufacturing ban in the mid-1970's, PCBs remain ubiquitous in the environment. In the Laurentian Great Lakes of the Midwest. PCBs and other toxic compounds contaminate bottom sediments at almost all designated "areas of concern" (AOC)(figure 1, upper left inset). The International Joint Commission, a binational group from Canada and the United States, has identified these AOCs in their efforts to restore and protect Great Lakes ecosystems. One such area, the Fox River which flows into Green Bay, has been the focus of much scientific study in an effort to improve not only that river but to apply lessons learned to other AOCs. The final goal is a healthy Great Lakes food chain with fish and waterfowl that are safe to consume.

Fox River, Great Lakes, Lake Winnebago↗